SWA cable to sub board

[brigstockes]

Hi, I need to run a second 100a board into an extension approx 25m from the supply and existing board, I am happy after speaking to the DNO that no new supply is required and that I can henley the tails but ideally would like to run a cable in a trench the 25 meters to the new board location. I was going to use 25mm 3c swa, using one of the cores as earth, fitting an isolator to the supply side. Does this sound ok? any advice gratefully received.

 

[micknew]

Not really a DIY job!

 

[brigstockes]

Thanks I agree, I am a domestic installer but not got much experience with SWA, hence the advice

 

[yellowvanman]

25mm 3 core if you have to continue bonding into the extension, 2 core if you don't need to (cheaper). Make sure you gland/earth the SWA at its source (as a minimum). Must be a big extension to need 100A?

 

[brigstockes]

Thanks for the confirmation, it is a big extension the size of a large 3 bed house on its own!

 

[mogga]

as said this isnt a Electrical Trainee job not Isolator but what the BGB recomends to cover cant answer what you need as i havent seen installation